Goodwill and Intangible Assets - Changes in Goodwill (Detail) $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($)
Goodwill [Roll Forward]
Net goodwill, beginning balance	$ 1,662.3
Impact of changes in foreign currency	(5.0)
Net goodwill, ending balance	1,683.5
A&S Business [Member]
Goodwill [Roll Forward]
Net goodwill, ending balance	1,486.4
Measurement period adjustment related to acquisition of A&S	26.2
Power Transmission Technologies [Member]
Goodwill [Roll Forward]
Net goodwill, beginning balance	410.2
Impact of changes in foreign currency	(2.0)
Net goodwill, ending balance	408.2
Automation & Specialty [Member]
Goodwill [Roll Forward]
Net goodwill, beginning balance	1,252.1
Impact of changes in foreign currency	(3.0)
Net goodwill, ending balance	1,275.3
Automation & Specialty [Member] \| A&S Business [Member]
Goodwill [Roll Forward]
Measurement period adjustment related to acquisition of A&S	$ 26.2

Goodwill foreign currency divestiture and other adjustments.

No definition available.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
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- Definition

Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 16
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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